library /*isNonNullableByDefault*/;
import self as self;
import "dart:core" as core;

abstract class Base extends core::Object /*isMixinDeclaration*/  {
  method methodWithDefaultImpl() → core::Object? {}
}
abstract class TestFailure<A extends core::Object? = dynamic> extends self::Base /*isMixinDeclaration*/  {
  @#C1
  abstract method methodWithDefaultImpl({covariant-by-class self::TestFailure::A? nameParam = #C2}) → core::Object?;
}
static method main() → void {}

constants  {
  #C1 = core::_Override {}
  #C2 = null
}